Serum IgG Concentrations after Intravenous Serum Transfusion in a Randomized Clinical Trial in Dairy Calves with Inadequate Transfer of Colostral Immunoglobulins

Background: Plasma transfusions have been used clinically in the management of neonates with failure of passive transfer. No studies have evaluated the effect of IV serum transfusions on serum IgG concentrations in dairy calves with inadequate transfer of passive immunity.
Hypothesis: A commercially available serum product will increase serum immunoglobulin concentration in calves with inadequate transfer of colostral immunoglobulins.
Animals: Thirty-two Jersey and Jersey-Holstein cross calves with inadequate colostral transfer of immunoglobulins (serum total protein <5.0 g/L).
Methods: Thirty-two calves were randomly assigned to either control (n = 15) or treated (n = 17) groups. Treated calves received 0.5 L of a pooled serum product IV. Serum IgG concentrations before and after serum transfusion were determined by radial immunodiffusion.
Results: Serum protein concentrations increased from time 0 to 72 hours in both control and transfused calves and the difference was significant between the control and treatment groups ( P < .001). Mean pre- and posttreatment serum IgG concentrations in control and transfused calves did not differ significantly. Median serum IgG concentrations decreased from 0 to 72 hours by 70 mg/dL in control calves and increased over the same time interval in transfused calves by 210 mg/dL. The difference was significant between groups ( P < .001). The percentage of calves that had failure of immunoglobulin transfer 72 hours after serum transfusion was 82.4%.
Conclusions and Clinical Importance: Serum administration at the dosage reported did not provide adequate serum IgG concentrations in neonatal calves with inadequate transfer of colostral immunoglobulins.     

牛胎衣不下的研究进展

本文就牛胎衣不下的发生原因和机制。从胎衣不下与过氧化物和过氧化氢酶,与间质酶,与碱性磷酸酶和脱氢酶以及胎衣不下与免疫的关系四个方面进行了综述。介绍了胎衣不下的研究进展。     

Simulation analysis of the effect of herd immunity and age structure on infection of a cattle herd with bluetongue viruses in Queensland, Australia

A state-transition model based on Leslie matrix formulation was used to investigate the effects of herd immunity and age structure on the infection of a simulated cattle herd with bluetongue viruses under Australian climatic conditions. Increasing duration of immunity decreased the prevalence of infection. A duration of immunity of 33 months was consistent with prevalence estimates made from previous serological studies of bluetongue virus. Herd prevalence displayed slowly dampening cyclical variation over time (most pronounced when a short duration of immunity was simulated). Increasing calving and mortality risk rates in the simulated herd increased prevalence, whereas increasing age at first calving decreased prevalence. Manipulation of calving rates had the greatest effect on the predicted prevalence of infection in the herd. Simulation of a number of herd-management scenarios suggested that management systems in which cattle are bred early and where high calving rates are achieved are likely to contribute to high levels of infection with bluetongue viruses. Results confirm the importance of management factors in influencing the prevalence of infectious diseases in animal populations.     

Mortality and commercial off-take rates in adult traditional cattle of Zambia

A cohort study was conducted in the livestock-wildlife interface areas of Zambia to determine cattle mortality and commercial off-take rates among adult cattle as well as factors influencing them. A total of 416 animals from 43 herds were followed up for one year and animals were individually identified and their fate was indicated as sold, slaughtered, dead or present as appropriate. The overall mortality incidence risk was estimated at 7.5%. Cattle in Kazungula were at a greater risk of dying compared to those in Blue Lagoon and Lochnivar. Annual off-take was estimated at 13.7% (8.1–19.3%), unadjusted values, and 16.4% (8.1–24.5%) after adjusting for sampling fraction in primary sampling units (herds) and area stratification. Area variations were observed with Kazungula recording the highest in both instances, which was attributed to a contagious bovine pleural pneumonia (CBPP) outbreak. Herd size and gender were observed to influence cattle mortality rates. Cattle in the middle-sized herds (50–150 cattle) recorded high mortality rates (OR = 3.91) compared to smaller herds (10–50) and so were females compared to males (OR = 4.16). The logistic regression model showed that cattle death was influenced by managerial factors and that off-take rates tend to increase in the face of disease outbreaks.     

Calf mortality rate and causes of death under different herd management systems in peri-urban Bamako, Mali

Calf mortality rate and causes of death were studied in peri-urban livestock production systems in Bamako, Mali, for calves born and dying from November 2002 to March 2004. Causes of death for 93 deceased calves were diagnosed from clinical autopsies, reported history of death and parasitic information. Calves originated from traditional, modernized and station management systems. Overall mortality rate was 17% during the first year of life (N = 756 live-births). Mortality rate was significantly lower for traditionally (10%) compared to modernized (19%) or to station managed calves (25%). Total perinatal loss (abortions + stillbirths + perinatal mortality) was 5% (N = 784 gestations). The most important death categories were digestive tract disorders (28%), perinatal mortality (16%) and accidents (14%). Vector-borne and infectious diseases were of low importance. Digestive tract disorders and perinatal mortality were the most important categories of death in modernized management while accidents and starvation were the most important causes of death in traditional management. Digestive tract disorders were more common in modernized than in traditional management (p = 0.02), revealing a serious problem with hygiene in stationary enclosures. With better calf management in regard to hygiene, surveillance and control of milk off-take, overall calf survival may be increased and peri-urban livestock production made more profitable.     

Factors related to the risk of neonatal mortality,birth-weight and serum immunoglobulin concentration in lambs in the UK

Neonatal-lamb mortality represents an economic loss and welfare concern. Two factors often associated with the risk of mortality are birth-weight and serum immunoglobulin concentration. We used data from two studies to investigate risk factors for mortality between 2 and 14 days of age and factors affecting birth-weight and serum immunoglobulin concentration at 48 h of age. Dataset 1 included 1339 lambs born on eight farms during the 1995 spring lambing season; dataset 2 included 3172 lambs on seven farms during the 1991 spring lambing season. To account for some of the potential clustering within the data, multilevel models were used. Most (>75%) of the variation in the risk of mortality was at the lamb level. In dataset 1, factors significantly associated with increased odds of lamb mortality included low birth-weight and low serum immunoglobulin concentration. In dataset 2, significant risk factors for mortality included low birth-weight, ewe body-condition score, being born late in the season (relative to other lambs on the farm) and being born in multiple litters. There was a significant interaction between the effects of litter size and birth-weight. (Serum immunoglobulin concentration was not available for dataset 2.) More than half of the variation in birth-weight was at the ewe level, 27% at the lamb level, and 18% at the farm level (dataset 1). Single birth and being male were associated with increased birth-weight in both datasets. In dataset 2 only, increasing ewe condition score and birth early in the study period were also associated with increased birth-weight. Fifty-six percent of the variation in immunoglobulin concentration was at the lamb level, 36% at the ewe level and only 7% at the farm level. Factors associated with reduced serum immunoglobulin concentration included early or late birth in the lambing season, being born later than 14 days after the first lamb born on the farm, multiple-birth litters and maternal mastitis.     

牛双胎的研究与应用

牛双胎可显著的提高生产效率,对母牛和犊牛没有明显的不良影响,不利之处是异性双胎造成母犊不孕、。双胎是可以遗传的,双亲的影响较大;不同品种间的双胎率差异显著;另外胎次、季节、营养均影响双胎率。目前常用的提高双胎率的方法是通过遗传选择、激素诱导、激素免疫、胚胎移植等方法。但如果结合标记辅助选择法（MAS）、性别控制、及转基因与克隆技术将有助于快速提高双胎率,提高生产效益。     

我国肉牛生产发展之管见

本文通过对目前我国肉牛生产发展概况的介绍并与世界主要国家和地区情况的对比,阐述了自己对核问题的看法。对存在问题的原因进行了初步分析,并提出了建设性意见。     

河南省三种地方牛种超数排卵结果与分析

［目的］为了分析河南三种肉牛超数排卵效果。［方法］分别选择夏南牛、郏县红牛、南阳牛作为试验母牛,采用两次PG+促卵泡素(FSH)的方法对试验母牛进行超数排卵,观测试验母牛获得总胚胎数、可用胚数分析超数排卵效果。［结果］结果显示,夏南牛可用胚9.86枚/头,南阳牛可用胚7.71枚/头,郏县红牛为6.75枚/头,可用胚中夏南牛最高与郏县红牛和南阳牛有显著性差异。可用胚率郏县红牛最高79.41%,显著高于夏南牛和南阳牛。［结论］结果表明,PG+FSH法可以用于夏南牛、郏县红牛和南阳牛的超数排卵。     

猪场免疫失败常见因素分析

免疫是预防猪发生传染病的主要手段。近年来国内外对猪的各种疾病进行了预防接种,收到了一定的效果。但免疫后发病的现象也时有发生,给养猪业造成不可估量的损失,并因此而引发多起民事纠纷。本文根据实践经验,对免疫失败的因素详细分析,以帮助养猪户合理防疫,提高养殖效益。     

利用关岭牛及其杂交牛生产雪花牛肉的试验研究

选择8～10月龄的关岭牛、西×关杂交牛（西门塔尔牛♂×关岭牛♀）、安×关杂交牛（红安格斯牛♂×关岭牛♀）、利×关杂交牛（利木赞牛♂×关岭牛♀）各8头,进行育肥生产雪花牛肉的试验研究。结果表明：在同一饲养管理条件下,西×关杂的宰前活重、屠宰率、净肉率、肉骨比值、眼肌面积、高档肉块重最高,依次为利×关杂、安×关杂、关岭牛;西×关杂组、利×关杂组、安×关杂组的宰前活重、眼肌面积和高档肉块重差异不显著（P〉0．05）,但均显著高于关岭牛组（P〈0．01）;关岭牛组和安X关杂组的肌内雪花状脂肪含量均为3级,优于西×关杂组和利×关杂组;综合评价关岭牛组和安×关杂组的胴体等级均为3A级,西×关杂和利×关杂的胴体等级均为2A级。结果显示,关岭牛虽然产肉性能不高,但机体内并不缺少优秀的遗传基因,具备选育成优质高产肉牛品种的种质基础。     

我国秦川牛等四品种黄牛屠宰试验报告

本屠宰试验所用良种黄牛品种系鲁西牛(25头)、秦川牛(29头)、晋南牛(28头)、南阳牛(26头)4个品种共108头。屠宰前平均活重(未停水停食处理)为554.15±67.6kg;屠宰率达63.30±1.84％;净肉率为53.65±2.34％;可供4～5星级饭店的高档牛肉重约占活重的5.2％,其产值却可占总产值的46％以上。经北京市4～5星级饭店品尝、试用、使用,各用户一致认为牛肉品质已达到进口的同类产品的最优等级,完全可以取代进口牛肉。     

“新晃黄牛”肉质特性研究

本试验随机选取新晃黄牛和湘西黄牛各6头,分别测定了新晃黄牛和湘西黄牛肉的理化性质、化学成分及氨基酸和维生素等组成。与湘西黄牛相比,新晃黄牛肌肉中脂肪含量低,差异极显著(P﹤0.01);股二头肌的粗蛋白含量低,差异显著(P﹤0.05);天冬氨酸、谷氨酸、苏氨酸、精氨酸、丙氨酸、缬氨酸含量高,差异极显著(P﹤0.01);维生素B2和维生素B6含量高,差异极显著(P﹤0.01);钙和锰含量高,差异极显著(P﹤0.01);镁含量高,差异显著(P﹤0.05)。由此可见,新晃黄牛肉肉质细嫩、香味浓郁、风味独特、营养价值高,是养生、健体的健康食品。     

科学发展肉牛生产 积极迈向市场经济

山西万荣近年在发展商品生产过程中,由于认真贯彻了大抓饲草基地建设和秸秆氮化养牛;提高冷配技术,搞好畜种改良;调整牛群结构,提高商品牛的出栏率;实行科学饲养,提高经济效益;制定优惠政策,调动群众积极性;以加促养,实行“产、供、销”一条龙服务等六项措施,从而到１９９２年,全县黄牛发展到８．９万头,户均１．２头,比１９８６年增长１５．７％;６年间共出售商品牛１２．３万头,年均出栏率２４．６％。出集商品牛     

务川黑牛品种简介

就务川黑牛的分布、品种特性、适应性、抗病力、生产性能等进行了详细的介绍。     

Impact of milking characteristics and morphology of udder and teats on clinical mastitis in first- and second-lactation Norwegian cattle

Data from the Norwegian progeny testing program were used to examine the impact of milking characteristics and morphology of udder and teats on clinical mastitis in first- and second-lactation Norwegian cattle. The study was designed as a 1-1 matched case-control study with herd, parity, days in lactation and calving season as matching variables. Conditional maximum likelihood logistic regression was used to evaluate the effects of three primary (2 min milk, milk leakage and teat-end-to-floor distance) and six other study variables. Treatment records from the Norwegian health card system on acute and chronic clinical mastitis were used to define cases. The chosen model included 565 matched pairs. Significant risk factors of clinical mastitis were decreasing teat-end-to-floor distance (P = 0.02) and periparturient udder edema (P < 0.01).

Borderline effects were demonstrated by larger than herd-average teat diameter (P = 0.04), udder asymmetry (P = 0.05) and increasing 2 min milk (P = 0.08). Results were compared to a previous study on the same data with log_e somatic cell count as the dependent variable. Inclusion of teat-end-to-floor distance in the genetic improvement scheme may increase the efficiency of genetic selection for mastitis resistance.